PROJECT SUMMARY Neurodegenerative disorders, stroke, and chronic pain are associated with ongoing neuroinflammation which can be partially ameliorated by endocannabinoids. Endocannabinoids are ligands for cannabinoid receptor 1 and 2 (CB1 and CB2). CB1 receptor agonists exhibit psychotropic properties while CB2 receptor agonists have anti-neuroinflammatory effects. Consequently, there is a strong interest in the discovery of CB2 selective agonists to mitigate inflammatory pathologies while being devoid of the psychotropic activity exhibited by CB1 receptor agonists. Endocannabinoids are derived from dietary fatty acids. Anandamide (AEA) is derived from the ?-6 fatty acid arachidonic acid (AA), while docosahexaenoic ethanolamide (DHEA) is derived from the ?-3 fatty acid, docosahexaenoic acid (DHA). The ?-3 and ?-6 endocannabinoids AEA and DHEA are further metabolized by eicosanoid synthesizing enzymes such as CYP epoxygenases to form oxidized endocannabinoid products that have new biological activity. Previous studies have shown that CYP epoxygenases convert AEA into AEA-epoxide that is a CB2 selective agonist. Herein we will test our central hypothesis that, DHEA epoxide (EDP- EA) will display anti-neuroinflammatory action in microglial cells by binding to CB2 receptor and other putative receptors. In order to execute the specific aims of this proposal, we will use a combination of several innovative methods including novel targeted lipidomics (LC-MS/MS) approaches to detect lipid epoxide metabolites, receptor binding and activation studies and neuroinflammation studies using microglial cells. The overall outcome of the project will be the discovery of a new set of lipid signaling endogenous molecules, DHEA epoxides that exhibit anti-neuroinflammatory properties.